Qualtech 29 piece 135 degrees split point heavy duty drill bit set comes in a metal case. Manufactured to National Aerospace standard 907. Made of heat resistant cobalt, they display higher red hardness which permits speeds upto 30 percent greater than High-Speed Steel drills and are especially effective in drilling tough, high tensile strength materials like PH stainless steel, inconel, and titanium. These drills are self-centering and reduces thrust. Sizes smaller than 1/16-inches have the 118 degrees standard point. Cobalt steel tools are similar to high-speed steel, but with more cobalt for improved performance when cutting harder metals such as stainless steel or nickel alloys. Gold oxide is a thinner oxide surface treatment than black oxide typically used to identify cobalt steel tools; performance is similar to uncoated tools. Round shanks allow use with a wide variety of toolholding systems. When run in a counterclockwise direction (right-hand cut) spiral fluted tools evacuate chips up and out of the cut to reduce clogging. Set include fractional sizes: 1/16″ to 1/2″ (1/64 Increments). Set of 29 jobber length drill bits includes inch sizes 1/16″ to 1/2″ in 1/64 increments Cobalt steel provides extended tool life compared to high-speed steel drill bits when drilling hard materials Gold oxide finish lubricates the drill bit and provides wear resistance Self-centering 135-degree split point penetrates hard material without a pilot hole and produces small chips to reduce clogging Meets ANSI specifications.